Ingredients benefit bone health: Elevated sales of calcium supplements and fortified foods evidence concerns about osteoporosis, even as isoflavones and essential fatty acids join the battle

Prepared Foods, Feb, 2002 by Amanda Archibald

Next to general health and well being, and the sports nutrition category, osteoporosis was the leading condition that drove supplement purchases in 2000," said Danny Wells, president of Danny Wells Associates, Inc., during his keynote address at Natural Products Expo East, Washington D.C., this past fall. Validating this trend, sales data from the Hartman Group Inc.'s, Bellevue, Wa., 1999 Natural Products Census indicated that 4% of all consumers surveyed use supplements for osteoporosis. Roughly translated, more consumers are purchasing supplements for bone health than they are for colds.

Why the proliferation of food products and supplements targeting bone health? According to the National Institutes of Health Osteoporosis and Related Bone Disease National Resource Center, Washington D.C., osteoporosis and its complications are associated with annual health costs in excess of $14 billion. The condition constitutes a "major public health threat" and currently affects 10 million individuals directly, with an additional 18 million at risk for the disease due to low bone mass. Osteoporosis is a largely preventable disease. The industry is taking note.

The science behind the shelf life

Osteoporosis is characterized by decreased bone mass, or bone mineral density, and structural degradation of the bone tissue. Risk factors for developing osteoporosis include gender (female), age, family history, nutritional status, medication, hormone levels, smoking and excessive alcohol intake.

Bone tissue is a complex matrix of multiple nutrients. Nutrients may play a variety of roles to include direct involvement in bone tissue development, enzymatic activity contributing to bone tissue formation, or physiological regulation of hormones, nutrients and other factors involved in the bone remodeling process. Bone remodeling is a continual process of vital destruction and rebuilding of bone tissue and is sensitive to hormone and nutrient availability.

Calcium is widely recognized as the major nutrient player in bone health. Research also broadly documents the synergistic role between Vitamin D and calcium absorption (and subsequent availability for bone formation). Beyond these two major nutrients, extensive research implies a wide cross-section of nutrients and their positive or negative role in bone health. Positive associations include protein, magnesium, zinc, phosphorus, copper, manganese, boron, silicon and Vitamin K. Negative associations include sodium and excess protein. Essential fatty acids (EFA) in the form of eicosapentaeoic acid (EPA) and dihomogammalinolenic acid (DGLA) also have been shown to play a role in stimulating insulin-like growth factor (IGF) in growing rats. IGF is considered a powerful growth stimulator for bone. A definitive role for EFAs in human bone health in humans is still pending.

And the Soy Story

Soy isoflavones have been the center of much recent attention in bone nutrient research. Soy and its derivatives have had a conflicting research course. This is evidenced by a scientific community which remains cautious about defining exactly which components of soy germ play a role in bone health, what that role is and what mechanisms are in place. Soy research has suggested a positive correlation with bone mineral density and also with a reduction in the rate of bone loss among women traversing the menopause spectrum. Professor William Wong, Baylor College of Medicine, Waco, Tx., agrees that research using soy germ isoflavones has shown "promising" results in both pen- and post- menopausal females. While Wong has himself shown positive results using isoflavone supplementation, he admits that long-term studies are required to answer questions about the safety, efficacy and optimal dosage of isoflavones.

Evidence presented at the recent 4th International Soy Symposium also suggests a potentially different course for future soy research. According to Laurent LeDuc, general manager, Schouten Foods, two fundamental issues emerged. First: evidence suggests that it is the composition and synergy of the entire soy protein matrix, and not isolated components, that has positive effects on bone tissue. Secondly: some of the conflicting results obtained in the soy research area may be related to the ability of research subjects (women) to effectively metabolize soy (as indicated by urinary equol levels).

Industry's Response

The significance of osteoporosis and the NIH's "cry for attention" has been heard by the food and supplement industries. Current product trends are multi-nutrient formulations with structure/function claims promoting bone health across stages of the lifecycle. Take Avon Product's VitAdvance, or Nature Made's Calcium Plus Soy as examples. Both products contain more than one nutrient deemed to have a role in bone health. Both products target a stage in the feminine lifecycle. Other supplement products may contain additional herbal components such as black cohosh, red clover, horsetail, primrose oil, borage oil, soy isoflavones. The reason behind this? Provisional, or non-conclusive evidence suggesting their contributory role in bone metabolism and health, and their rich source of nutrients which may play a role in bone health.